JP4708798B2 - Battery cell holding member and battery module - Google Patents

Description

  The present invention relates to a battery cell holding member capable of integrating a plurality of battery cells, and a battery module in which a plurality of battery cells are integrated by the battery cell holding member.

In recent years, the development of electric vehicles and hybrid electric vehicles (hereinafter simply referred to as “electric vehicles and the like”) using an electric motor as a drive source has been rapidly advanced. The power source of an electric motor mounted on an electric vehicle or the like is required to be small and light in order to improve the steering characteristics of the electric vehicle or the like, one charging travel distance, and the like. In order to realize a power supply that meets such demands, a film-clad battery disclosed in Patent Document 1 and the like has been developed, and a desired output voltage can be obtained by accommodating a large number of this type of film-clad battery in a case. Battery packs (sometimes called “assembled batteries”) have been developed. FIG. 5 shows a basic structure of a film-clad battery disclosed in Patent Document 1 and the like. In this film-clad battery 100, a power generation element 101 made of a positive electrode side active electrode, a negative electrode side active electrode, and an electrolytic solution is covered with a laminate film 102 formed by laminating a metal film such as aluminum and a heat-fusible resin film. It has been done. Note that the four opposing sides of the two laminated films 102 covering the power generating element 101 are hermetically sealed by heat sealing. A film-like positive electrode terminal 103 is drawn from one short side of the heat-bonded laminate film 102, and a film-like negative electrode terminal 104 is drawn from the other short side.
JP 2001-76691 A

  The output voltage per film-clad battery is about 3 to 4 [V], and in order to obtain a practical output voltage, it is necessary to electrically connect a number of film-clad batteries in series. When the number of film-clad batteries increases, it takes time to mount, transport, and store. For example, in order to run an automobile with an electric motor, a voltage of about 300 to 400 [V] is generally required. Therefore, in order to obtain the required voltage, about 100 film-covered batteries are required, and it is very difficult to handle a large number of these film-covered batteries in a disassembled state, and it takes time and effort to assemble the battery pack. .

  This invention is made | formed in view of the said subject, The objective is to improve the convenience at the time of handling a lot of film-clad electrical devices by modularizing a film-clad electrical device for every predetermined number. is there.

  The battery cell holding member of the present invention is a battery cell holding member that integrally holds a plurality of battery cells in which a film-clad battery is housed in a cell case, and houses a plurality of battery cells stacked in the thickness direction. Possible first accommodation space and second accommodation space, a partition that separates the first accommodation space and the second accommodation space in the stacking direction of the battery cells, and accommodation in the first and second accommodation spaces And a holding portion capable of restricting the movement of the battery cell in a direction orthogonal to the stacking direction of the battery cells.

  The holding portion can be formed with an engaging portion that can engage with a corner portion of the cell case. Moreover, the screw hole for fixing the electrically-conductive member for electrically connecting the battery cells laminated | stacked can also be formed.

  By adding a lid member addressed to the battery cell accommodated in the first and second accommodation spaces, the battery cell laminated between the lid member and the partition portion is sandwiched in the lamination direction. You can also.

  According to the present invention, a predetermined number of film-clad batteries are integrated. Therefore, when handling a large amount of film-covered batteries, it is very convenient in many cases such as transportation, storage and the like as compared with the case where they are separated.

  Hereinafter, an example of an embodiment of a battery module of the present invention will be described in detail with reference to the drawings. FIG. 1 is an external perspective view of the battery module 1 of this example. FIG. 2 is an exploded perspective view of each battery cell 2 constituting the battery module 2. 3 and 4 are exploded perspective views of the battery module 1.

  As shown in FIG. 1, the battery module 1 of the present example includes a conductor member (bus bar 5) in which a plurality of battery cells 2 are integrated (modulated) by a holding member 3 and the battery cells 2 are fixed to the holding member 3. ) In series.

  First, the structure of the battery cell 2 will be described in detail with reference to FIG. The battery cell 2 is one in which the film-clad batteries 6 are housed in the cell case 7 one by one. The film-clad battery 6 is a battery in which a power generation element (not shown) having a positive electrode side active electrode, a negative electrode side active electrode, and an electrolyte solution is hermetically packaged by two laminate films 8 and has an output voltage of about 3.6 [V ]. The laminate film 8 is a film in which a metal film such as aluminum and a heat-sealable resin film are overlapped, and the four opposing sides of the two upper and lower laminate films 8 surrounding the power generation element are heated. It is hermetically sealed by fusion.

  The power generation element of the film-clad battery 6 includes a laminated type composed of a positive electrode side active electrode and a negative electrode side active electrode laminated via a separator, and a strip-like positive electrode side active electrode and a negative electrode side active electrode via a separator. After winding this, there is a winding type in which positive electrode side active electrodes and negative electrode side active electrodes are alternately stacked by compressing in a flat shape, and the power generation element of the film-clad battery 6 shown in FIG. Any of the laminated type and the wound type may be used. Furthermore, a positive electrode plate and a negative electrode plate used in a general lithium ion secondary battery can be used for the positive electrode side active electrode and the negative electrode side active electrode. That is, a positive electrode plate in which a positive electrode active material such as lithium-manganese composite oxide and lithium cobaltate is applied on both surfaces of an aluminum foil, and a negative electrode in which a carbon material capable of doping and undoping lithium is applied on both surfaces of a copper foil The power generation element can be obtained by making the plate face each other via a separator and impregnating the plate with an electrolytic solution containing a lithium salt. However, the power generation element only needs to include a positive electrode, a negative electrode, and an electrolyte, and any power generation element used in a normal battery can be applied as it is or with an appropriate design change.

  Referring to FIG. 2 again, the positive electrode terminal 10 connected to the positive electrode side active electrode is drawn out from one short side of the film-clad battery 6, and the negative electrode side active electrode is drawn from the other short side. The connected negative electrode terminal 11 is drawn out. The materials for the positive electrode terminal 10 and the negative electrode 11 are selected in consideration of their electrical characteristics. In this example, aluminum is used for the positive electrode terminal 10 and copper or nickel is used for the negative electrode terminal 11. It was.

  The cell case 7 includes a case body 12 and a frame body 13. The case body 12 includes a bottom plate 15 having a substantially frame shape and a side wall 16 raised from the periphery of the bottom plate 15, and has a dimension capable of accommodating the film-clad battery 6 inside the side wall 16. On the other hand, the frame 13 has a shape and size that can be fitted inside the side wall 16 of the case main body 12, and covers the film external battery 6 accommodated in the case main body 12, so that the film external battery 6 The periphery is sandwiched between the bottom plate 15 of the main body case 12. Further, seven through holes 17 are formed in the bottom plate 15 of the case body 12. These through-holes 17 are formed at positions that do not overlap with the film-clad battery 6 housed in the case body 12 and the frame body 13 covered on the film-clad battery 6, and the cell case 7 has a thickness thereof. Designed to communicate in the direction. The positive electrode terminal 10 and the negative electrode 11 of the film-clad battery 6 accommodated in the cell case 7 are respectively connected to the outside of the cell case 7 through two notches 18 provided on the short side of the case body 12. Has been pulled out.

  Next, the structure of the holding member 3 will be described in detail with reference to FIGS. 3 and 4. The holding member 3 includes a partition portion 20 and a holding portion 21 that are integrally formed of synthetic resin. The partition portion 20 has a plate shape substantially similar to the cell case 7 shown in FIG. 2, and has three long holes 22 formed at predetermined intervals along the longitudinal direction in one long side portion, and the other long side. Four through holes 22 are formed in the part. On the other hand, the holding portion 21 extends from the four corners of the partition portion 20 in the axial direction of the through hole 22. In other words, the partition part 20 divides the space surrounded by the four holding parts 21 at the center in the longitudinal direction of the holding part 21 to form the first accommodation space 23 and the second accommodation space 25. ing. Furthermore, an engaging groove 26 that can engage with a corner portion of the battery cell 2 (cell case 7) is formed along the longitudinal direction on the inner side surface of the holding portion 21, and both ends of the engaging groove 26 are held in the holding direction. An opening is formed at the end surface 27 of the portion 21. In addition, a large number of reinforcing ribs are formed on the outer surface of the holding portion 21 and screw holes (not shown) to which the bus bars 5 attached to the electrode terminals 10 and 11 (FIG. 2) of each battery cell 2 are fixed. Is formed.

  In order to integrally hold the plurality of battery cells 2 using the holding member 3 having the above-described structure, the following is performed. First, as shown in FIG. 3, twelve battery cells 2 are stacked in the thickness direction, and the positive electrode terminal 10 and the negative electrode terminal 11 of the adjacent battery cells 2 are connected via the bus bar 5. Two battery cell groups A and B are formed. Here, since the output voltage of each battery cell 2 is about 3.6 [V], the output voltage of the battery cell groups A and B in which 12 battery cells 2 are connected in series is about 43.2 [V]. .

  Next, one battery cell group A is accommodated in the first accommodating space 23 of the holding member 3, and the other battery cell group B is accommodated in the second accommodating space 25. At this time, the battery cell groups A and B are inserted into the first accommodation space 23 or the second accommodation space 25 from the end surface 27 side of the holding portion 21 according to the guide of the engaging groove 26 formed in the holding portion 21. . At this time, as shown in FIG. 4, metal rods 30 are passed through the through holes 22 of the partition portion 20 in advance, and the rods 30 are respectively inserted into the first accommodation space 23 and the second accommodation space 25. It passes through the through hole 17 (FIG. 2) of each cell case 7 of the battery cell groups A and B to be inserted.

  Referring to FIG. 3 again, when the battery cell groups A and B are accommodated in the first accommodation space 23 and the second accommodation space 25, the bolts corresponding to the through holes 17 from the outside of the battery cell groups A and B, respectively. The cover plate 32 in which the through holes 31 are formed is directed to the outermost battery cell 2 in the stacking direction. The cover plate 32 has a plate-like form substantially similar to the partition portion 20, and the battery cell group A, the corner portions of the four corners are fitted into the engagement grooves 26 from the end surface 27 side of the holding portion 21. It can be inserted into the first accommodation space 23 or the second accommodation space 25 in the same manner as B. Here, the distance L from the surface of the partition part 20 to the end face 27 of the holding part 21 is substantially the same as the sum of the thicknesses of the 12 battery cells 2 stacked and the thickness of the cover plate 32. Therefore, when the cover plate 32 is placed outside the battery cell groups A and B housed in the first and second housing spaces 23 and 25 as described above, the surface of the cover plate 32 and the holding portion 21 The end surface 27 is substantially flush (see FIG. 1). Further, the length of the rod 30 is set such that the end surface of the rod 30 only comes into contact with the peripheral edge of the corresponding bolt through hole 31 of the cover plate 32 and is not inserted into the bolt through hole 31. Therefore, as shown in FIG. 4, the bolt 33 inserted into the bolt through hole 31 is screwed into a screw formed on the inner peripheral surface of the rod 30 to fix the cover plate 32. Accordingly, the battery cell groups A and B accommodated in the first and second accommodation spaces 23 and 25 are sandwiched between the partition portion 20 and the lid plate 32, respectively. The pressure acting on the battery cell groups A and B can be managed by adjusting the tightening torque of the bolt 33.

  The number of battery cells 2 constituting the battery cell groups A and B is not limited to twelve. However, from the viewpoint of safety, it is desirable to set the number of battery cells 2 so that the output voltages of the battery cell groups A and B are 50 [V] or less. When the number of battery cells 2 constituting the battery cell groups A and B is changed, or when the thickness of each battery cell 2 is changed even if the number is the same, the holding unit 21 is changed accordingly. It is desirable to appropriately change the length of.

  It is obvious from the above description that the battery module of the present invention can constitute a battery pack (assembled battery) that can obtain a desired output voltage by connecting a plurality of them in series or in parallel. For example, if four battery modules 1 of this example are connected in series, an electric pack (assembled battery) capable of outputting a voltage of 300 [V] or more required for running an automobile by an electric motor can be obtained. In this case, it is desirable from the viewpoint of safety that the battery cell groups A and B in each battery module 1 are electrically connected in the final stage of assembling the battery pack, and the battery modules 1 are further electrically connected. This is because according to the above work process, as many work processes as possible can be completed with the voltage as low as possible.

It is an external appearance perspective view which shows an example of embodiment of the battery module of this invention. It is a disassembled perspective view of the battery cell which comprises the battery module shown in FIG. It is a disassembled perspective view of the battery module shown in FIG. FIG. 4 is an exploded perspective view of the battery module shown in FIG. 1, and is an exploded perspective view in which a part different from FIG. 3 is omitted. It is a perspective view of a film exterior battery.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery module 2 Battery cell 3 Holding member 5 Bus bar 6 Film exterior battery 7 Cell case 8 Laminated film 10 Electrode terminal for positive electrodes 11 Electrode terminal for negative electrodes 12 Case main body 13 Frame 15 Bottom plate 16 Side wall 17 Through-hole 18 Notch 20 Partition part DESCRIPTION OF SYMBOLS 21 Holding part 22 Through-hole 23 1st accommodating space 25 2nd accommodating space 26 Engaging groove 27 End surface 30 Rod 31 Bolt through-hole 32 Cover plate 33 Bolt A Battery cell group B Battery cell group

Claims (8)

A battery cell holding member that integrally holds a plurality of battery cells in which a film-clad battery is housed in a cell case,
A first housing space and a second housing space capable of housing the plurality of battery cells stacked in the thickness direction;
A partition that separates the first housing space and the second housing space in the stacking direction of the battery cells;
A battery cell holder having a holding part that abuts on the outer surface of the battery cell housed in the first and second housing spaces and can regulate the movement of the battery cell in a direction orthogonal to the stacking direction. Element.   The battery cell holding member according to claim 1, wherein the holding portion is formed with an engaging portion capable of engaging a corner portion of the cell case.   The battery cell holding member according to claim 1 or 2, wherein a screw hole for fixing a conductive member for electrically connecting the stacked battery cells to each other is formed in the holding portion.   The battery cell holding member according to any one of claims 1 to 3, further comprising a lid member capable of sandwiching the battery cell accommodated in the first and second accommodation spaces with the partition portion.   5. The battery according to claim 1, wherein the first and second accommodation spaces are capable of accommodating a number of the battery cells having a total output voltage of 50 [V] or less in a stacked state. Cell holding member.   The said holding | maintenance part is extended in the stacking direction of the said battery cell accommodated in the said 1st and 2nd accommodation space from the four corners of the said partition part. Battery cell holding member.   A battery in which a plurality of the battery cells are housed in a state of being stacked in the thickness direction in the first and second housing spaces provided in the battery cell holding member according to claim 1. module.   A plurality of battery cells accommodated in the first and second accommodation spaces are electrically connected via a conductive member, and the conductive member is screwed to the holding portion provided in the battery cell holding member. Item 8. The battery module according to Item 7.

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